<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">DEPARTMENT OF COMPUTER SCIENCE </div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="khtml-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">UNIVERSITY OF CHICAGO</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Date: Monday, February 11, 2008</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Time: 2:30 p.m.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Place: Ryerson 251, 1100 E. 58th St.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">-------------------------------------------</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><br class="webkit-block-placeholder"></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" color="#272727">Speaker: Emanuele Viola</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" color="#272727"><br></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" color="#272727">From:</font><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#272727"> Columbia </font></span><font class="Apple-style-span" color="#272727">University</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" color="#272727"><br class="webkit-block-placeholder"></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" color="#272727">Web page: <a href="http://www1.cs.columbia.edu/~viola/">http://www1.cs.columbia.edu/~viola/</a></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font class="Apple-style-span" color="#272727"> </font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><span style=""><font class="Apple-style-span" color="#272727">Title: <span class="Apple-style-span" style="color: rgb(0, 0, 0); ">Lower Bounds</span></font></span></div>
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text-autospace:none"><font class="Apple-style-span" color="#272727">Abstract: <span class="Apple-style-span" style="color: rgb(0, 0, 0); ">Efficient computation is an ubiquitous phenomenon in nature, and of increasing relevance to many fields such as economics, biology, and mathematics. In this talk we survey some of our results about proving lower bounds, i.e. establishing that some explicit functions cannot be computed with limited resources. We explore various resources such as communication, time, circuit depth, and randomness, highlighting surprising connections among them.</span></font></p><br>In particular, we consider the fundamental problem of following a path in a graph whose edges are distributed among several collaborating players. We obtain a lower bound on the amount of communication that the players need to exchange, answering a decade-old question. We also exhibit lower bounds on the efficiency of error-correcting procedures, and present a recent result that formalizes the feeling that decoding is more difficult than encoding.
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mso-layout-grid-align:none;text-autospace:none">Host: Laci Babai</p><p class="MsoNormal" style="mso-pagination:none;tab-stops:28.0pt 56.0pt 84.0pt 112.0pt 140.0pt 168.0pt 196.0pt 224.0pt 3.5in 280.0pt 308.0pt 336.0pt;
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</div><div> <span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">Nita</font></p><p style="margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px Helvetica; min-height: 14.0px"><br></p><p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">**************************</font></p><p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">Nita Yack</font></p><p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">Departmental Administrator</font></p><p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">Computer Science Department</font></p><p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">1100 E. 58th Street - Room 151</font></p><p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">Chicago, IL 60637</font></p><p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">(773) 702-6019</font></p><p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">(773) 702-8487 FAX</font></p><p style="margin: 0.0px 0.0px 0.0px 0.0px"><br class="khtml-block-placeholder"></p><p style="margin: 0.0px 0.0px 0.0px 0.0px"><font class="Apple-style-span" face="Arial" size="4"><span class="Apple-style-span" style="font-size: 16px;; font-family: Arial; "><span class="Apple-style-span" style="font-family: Arial; font-size: 16px; "><span class="Apple-style-span" style="font-family: Arial; font-size: 16px; ">"Hard work spotlights the character of people: some turn up their </span></span></span></font><font class="Apple-style-span" face="Arial" size="4"><span class="Apple-style-span" style="font-size: 16px;; font-family: Arial; "><span class="Apple-style-span" style="font-family: Arial; font-size: 16px; "><span class="Apple-style-span" style="font-family: Arial; font-size: 16px; ">sleeves, some turn up their noses, and </span></span></span></font><font class="Apple-style-span" face="Arial" size="4"><span class="Apple-style-span" style="font-size: 16px;; font-family: Arial; "><span class="Apple-style-span" style="font-family: Arial; font-size: 16px; "><span class="Apple-style-span" style="font-family: Arial; font-size: 16px; ">some don't turn up at all."</span></span></span></font></p><br class="Apple-interchange-newline"></span></div></span> </div><br></body></html>